Ink-ribbon mechanism



April 23, 1929- J. s. DUNCAN ET AL INK RIBBON MECHANISM 5 sheets sheet 1Apr l 3, 19 9- J. s. DUNCAN ET AL INK RIBBON MECHANISM Filed Aug. 26,1925 5 Sheets-Sheet 2 April 23, 1929 J. s. DUNCAN ET AL 1,710,088

INK RIBBON MECHANISM Filed Aug. 26, 1925 s Sheets-Sheet 3 Patented Apr.23, 1929.

UNITED STATES PATENT OFFICE.

JOSEPH S. DUNCAN AND HENRY E. HUBBARD, OF CHICAGO, ILLINOIS, ASSIGNOBS,BY MESNE ASSIGNMENTS, TO ADDRESSOGRAPH COMPANY, OF CHICAGO, ILLINOIS, A

CORPORATION OF DELAWARE.

INK-RIBBON MECHANISM.

Application filed August 26, 1925. Serial No. 52,504.

- The object of this invention is to provide a mechanism of simplecol'istruction for feeding an ink ribbon step by step from one spool toanother and automatically reversing the feed when the ribbon has beenfed entirely from one spool and continuing automatically to reverse thefeed from one spool to the other during a continuous operation of themachine.

A further object of the invention is to provide a ribbon spool and atripping mechanism for cooperating therewith, these arts being of aspecial construction, where y a spool of a special construction may beused to cooperate with the tripper for automatically reversing the feedof the ink ribbon.

The invention has other objects in View which will appear hereinafter inthe detail description of the selected embodiment illustrated in theaccompanying drawings, in which Fig. 1 is a sectional elevationillustrating the improved feeding mechanism.

Figs. 2, 3 and 4 are detail views.

Figs. 5 and 6 show diiferent positions'of the feeding mechanism.

-Fig. 7 is a detail view.

Fig. 8 is a sectional view on the line ,88

of Fig. 1.

Fig. 9 is a sectional view on the line 9--9 of Fig. 1.

Fig. 10 is a sectional View on the line 10 10 of Fig. 1.

Figs. 11, 12, and 13 are detail views of the spool and driver.

Referring to the drawings, 14 represents the frame of a printingmachine, which may be of a type generally employed for printingaddresses on envelopes and the like. An ink ribbon 15 has its endsconnected to spools 16, 17. and travels back and forth across a bed 18and a platen 19 when in printing position. The spools 16, 17 are madealike and each is mounted on a driver 20, fast to a shaft 21, andprovided with a knob 21 (Fig. 12). The spool has one or more slots 22 inits side to register with slots 23 in the driver, and the latter alsohas a longitudinal groove 24 to receive the row of projections 25 on theinside of the spool which constitute a driving element engaging thedriver so that the latter may revolve the spool. The drivers are mountedin the frame 14 on opposite sides of printing position, and in parallelrela- Referring now to the right of Fig. 1, a. lever 28 is pivotallymounted at 29 upon the frame 14, and this lever carries betweewits endsone or more rollers 30 to engage the slots 22 of the spool and grooves23 of the driver. The lever 28 is normally held by a sprin 28" with therollers 30 in engagement wit the rlbbon on the spool or with the spool.A lever 31 (Fig. 3) is pivotally mounted at 32 on the frame 14 and ithas an arm 33 which carries a pivoted link 34, having a pin to engagethe teeth of the ratchet wheel 26 for turning the driver and spoolintermittently. A spring 34' engaging the link and the arm 33 normallyholds the pin 35 in operative engagement with the ratchet teeth. An arm36 on the lever 31 is connected by a link 37 with a sprlng pressed lever38 pivo'tcd at 38' on the frame of the machine and actuated by a cam 39.In the operation of the machine, the cam operates continuously, rockingthe lever 38 and imparting a rocking movement to the lever 31. Anotherarm 40 on the lever 31 projects upward and is connected by a rod 42 witha lever 43 pivoted at 43 on the frame 14. A pin 44 is slidably mountedin the lever 31 and is arranged to be engaged by the forward end 28 ofthe lever 28, to be thrust upward by said lever-28 into the path of aprojection 44 on a lever 45, Fig. 2, which is pivoted at 45' on theframe 14 and is connected at its lower end by a link 46 with a cam 47loosely mounted on the shaft of the edge of the teeth of the sprocketsto clear the pin 35 from the teeth of sprocket 26 and to clear acorresponding pin from the teeth of sprocket 27, the cams beingpositioned on their respective shaft-s so that they will be thrust inoperative position alternately.

An arm 50 on the lever 43, at the left of Fig. 1, carries a pivoted link51 which is rovided with a pin 52 to engage the teeth 0 the ratchet 27,being held by a spring 53 normally in operative engagement with theratchet. A lever 54 is pivoted at 54', on the frame 14 and has an arm 55which is arranged to engage a pin 56, Fig. 7, on the lever 43. Thislever 54 also carries one or more rollers 57 which are held by a s ring58, in operative engagement with the ri bon on the spool 17 or with thespool.

In practice the spool 16 or 17 is thrust over the knob 21' on to thedriver 20. The row of projections 25 must be registered with the groove24 so that the spool can be arranged in proper position on the driverwith the slots 22 registering with the grooves 23. To prevent the spoolfrom being put on the driver wrong end to I provide the spool with anextra projection 25' which is arranged to engage a recess 24 in thedriver, but this pro ection is spaced from the projections 25 so farthat it cannot enter the groove 24 and hence it is only possible toarrange the spool on its driver in its proper position. A catch 59,(Fig. 12) is carried by a stem 60 which projects through an enlargedopenlng 1n the spool and is fastened to the spool at 61. T1118 catch iscone shaped and the stem will yield to permit the arrangement of thespool on the driver, after which the catch will engage the end of thespool, as shown in Fig. 9, to hold the spool in place on the driver. The

lever 38 operates continuously during the operation of the machine andhence actuates the rod 42 and the parts connected therewith includingthe links 34 and 51 carrying the pins 35 and 52, the links and pinsconstituting feed pawls, which are arranged for operative engagementwith the teeth of the ratchet wheels. In Fig. 1 the ribbon is trav elingfrom right to left and the cam 47 is arranged to be engaged by the pin35 to clear the pin from the teeth of ratchet 26 so that this spool willidle. The rollers 30 are yieldingly held against the ribbon on the spooland act as a retarder to prevent loose unwinding of the ribbon. Duringthis operation while the spool 16 is idling, and acting as a supplyspool, the spool 17 is receiving the ribbon and acting as a take-upspool. The cam 49 is held out of the way of the pin 52 so that this pinengages the teeth of the ratchet 27 and causes the spool 17 to take upthe ribbon and feed it forward from the spool 16. When all the ribbon isfed off of the spool 16 the rollers 30 will enter the slots 22 of thespool 16 and the grooves 23 of the driver, being urged thereinto by thespring 28' acting on the lever 28. As this lever is thus rocked the arm28' will lift the pin 44 into the path of movement of the pro ection 44on the lever 45 so that on the next movement of the lever 31 the pin 44will engage the projection 44 and rock the lever 45 to shift the cams 47and 49 from the position shown in Fig. 1, where the ribbon is feedingfrom right to left to the position shown in Fig. 6, where the ribbon isfeeding from left to right. Fig. 5 shows the intermediate position wherethe ribbon has been fed off of the spool 16 and the tripper rollers haveentered the slots in the spool and the pin 44 has been lifted so that itwill engage the projection 44 on thenext operation of the lever 31 andshift the lever 45 and the cams connected therewith to the positionshown in Fig. 6. When the ribbon has been fed from the spool 17 to spool16, the lever 54 will be operated to thrust the pin 56 upward, where itwill engage the block 62 on the rod 48 and shift the cams to effectreversal of the feed. A stop 63 is provided on the frame to be engagedby the lever 45 for limiting the movement of the cam controlling means.Thus the ratchet pawls are continuously operating, but only the oneengages the ratchet where the cam is in inoperative position and theother pawl is prevented from engaging its ratchet by the cam being inoperative position where the pawl rides over the edge of the cam and isheld thereby away from the ratchet teeth. When the ribbon is exhaustedfrom one spool, the rollers enter the slots in the spool and the groovesin the driver and immediately there is a reversal of the feed of theribbon because, as before stated, the lever 38 is constantly operatingduring the operation of the machine and, consequently, the lever 31carrying the pawl 34, 35, and the lever 43 carrying the pawl 51, 52 arealso constantly operated, but the cams 47 and 49 control the pawls intheir operation of theratchets. It will be noted that the lever 31 andthe lever 43 act as bell crank levers, and that the lever 28 andthelever 54 are spring controlled and with the rollers and the arms 28, 55constitute trippers for effecting the reversal of feed of the ribbon. Y

We have illustrated the invention in a form which we have foundcommerciallv practicable and satisfactory, but we realize that changesin the form and proportion of parts and details of construction may bemade without departing from the spirit or sacrificing the advantages ofthe invention, and we reserve the right to make all such changes asfairly fall within the scope of the following claims.

We claim:

1. Ink ribbon mechanism comprising a rotatable driver having acircumferential groove, a hollow ribbon spool removably embracing thedriver in driving engagement therewith and having a circumferentlal slotregistered with the groove of the driver, and tripping mechanismincluding an anti-friction roller mounted to engage the periphery of arolled ribbon wound upon the s 001 and also disposed to enter the slotand groove when the ribbon has been unwound from the spool, a pawl forrotating said spool, and a cam for preventing the pawl from operatingthe ratchet when said roller enters the slot and groove.

2. Ink ribbon mechanism comprisin a rotatable driver g having acircumferential groove, a hollow ribbon spool in the form of a thin openended cylindrical shell removably embracing the driver in drivingengagement therewith and having a circumferential slot registered withthe groove of the driver, and tripping mechanism including ananti-friction roller mounted to engage the periphery of a rolled ribbonwound upon the spool and also disposed to enter the slot and groove whenthe ribbon has been unwound from the spool, a pawl for rotating saidspool, and a cam forpreventing the pawl from operating the ratchet whensaid roller enters the slot and groove.

3. Ink ribbon mechanism comprising a pair of slotted spools, an inkribbon connected at its ends to the spools, means for feeding the ribbonfrom one spool to the other and comprising a constantly operating feedpawl and a ratchet mechanism for each spool, and means for reversing thefeed of the ribbon comprising cams, and means for operating the cams toprevent cooperation of the pawl and ratchet of one spool while the pawland ratchet of the other spool are cooperative, a pair of trippers foractuating said reversing means, each tripper being mounted to enter theslot of its adjacent spool when the ribbon has been unwound therefrom tothereby control the reversing means, and to prevent cooperation of oneof said pawls with its cooperating. ratchet when the tripper has enteredsaid slot.

4. Ink ribbon mechanism comprising a pair of spools, an ink ribbonconnected at its ends to the spools, pawl and ratchet mechanism for eachspool, levers connected to said pawls and to each other for conjointoperation, means for rendering one pawl inoperative while the other pawlis operative, a tripper for each spool adapted to be operated when theribbon is unwound from the spool, a pin for each tripper adapted to beoperated thereby, and a device adapted to engage said pins to effect theshift of operation of the pawl controlling means.

slot and groove in the assembled condition of the spool and driver, anddisplaceable means to detachably retain the spool on the driver.

6. Ink ribbon mechanism comprising a ribbon spool having a slot therein,a driver adapted to receive said spool and having a groove to registerwith the slot in the spool, a tripper adapted to engage the slot andgroove, means to insure registration of the slot and groove in theassembled condition of the spool and driver, and displaceable means todetachably retain the spool on the driver.

7. Ink ribbon mechanism comprising a ribbon spool having a slot therein,a driver adapted to receive said spool and having a groove to registerwith the slot in the spool, a plurality of spaced projections on theinside of the spool and a longitudinal groove in the driver to makeinterlocking engagement between the spool and driver, and meansincluding a projection spaced from said other pro ections and adapted toengage said driver to permit the spool to be arranged in one positiononly on the driver.

8. Ink ribbon mechanism comprising a ribbon spool having a slot therein,a driver adapted to receive the spool and having a groove to registerwith the slot in the spool, a longitudinal groove in the driver, aplurality of spaced projections inside the spool to engage said groovefor interlocking the I spool and driver, and a separate projection inthe spool spaced from said other projections and adapted to engage aseparate recess in the driver to insure arrangement of the spool on thedriver in one position only.

JOSEPH S. DUNCAN. HENRY E. HUBBARD.

